TSSP: Input File Description

The input file contains a description of the solenoid or resonator. All the TSSP programs refer to this file for input. This page describes the format of the input file.

Updated: 19 Jul 2008

  Description

This is a plain ASCII text file which can be created and maintained using an ordinary text editor, or can be generated by a script according to some recipe. The file is stored in the working directory with a .in filename extension. When any of the TSSP programs are run with a system name, say, xyz, the program will look for an input file xyz.in. Syntax and grammar are intended to be straightforward and easy to extend as required in order to accomodate more detail as the modeling is refined.

Syntax

We use a straightforward syntax of white space separated fields, with "quoted text" recognised as a single field. A backslash escapes an end-of-line. A semicolon introduces a comment which is ignored to end-of-line. Otherwise free format. All text is case insensitive.

Grammar

The file is split into clauses delimited by curly brackets { }, which are contained between BEGIN and END keywords, so that the overall structure looks like 

BEGIN
 MODEL { ... }
 GROUND_PLANE { ... }
 PRIMARY {}
 SECONDARY { ... }
 TOROID { ...}
 ... others ...
END

in which the curly brackets contain parameters which describe that part of the resonator. The clauses don't have to be in the order shown above, and they don't all have to be there. Only the MODEL clause is mandatory, but it helps if you also have a SECONDARY.

The semantics of each clause are described below.

  Semantics

All dimensions are in metres. All heights are given relative to the ground plane.

The MODEL clause

Syntax:    MODEL { ... }
This contains a handful of setup commands relating to the model itself, as follows.

The GROUND_PLANE clause

Syntax:    GROUND_PLANE { ... }
Contains parameters describing the environment around the coil, not just the groundplane but walls, roof, etc, as well as extra things such as probe capacitance, load resistance, ground circuit resistance, etc.

The PRIMARY clause

Syntax:    PRIMARY { ... }

The SECONDARY clause

Syntax:    SECONDARY { ... }

The TOROID clause

Syntax:    TOROID { ... }
Parameters which describe a single toroid above the secondary.
  Examples
A simple high-Q secondary, outdoors, with no topload, fed via the base, and with a small adjustment to the top capacitance. 
BEGIN

model {
   gran 1       ; Going for high accuracy
   feed base
 }

ground_plane {
   ground_radius 2.0  ; A foil sheet
   ctop 5.2 pf        ; Adjust for scope probe capacitance
 } 

secondary {
   radius 0.295
   length 0.8
   height 0.15        
   use_lundin   
   turns 356
   resistance 3.65
   conductor 12 awg
 }

END

A large Tesla coil, with topload. 

BEGIN

model {
   gran 5    ; Modest resolution here
   feed primary
}

ground_plane {
   ground_radius 5
   wall_radius 5
   roof_height 6
  }

toroid {
   outer_radius 0.7575  ; Distance from center to outer rim.
   inner_radius 0.5575  ; Distance from center to inner rim.
   height 2.85        ; Distance of center above ground plane.
}

primary {
   radius1 0.275
   radius2 0.545
   height 1.035       ; A flat primary
   turns 9.5          ; The total available turns
   tap 8.2            ; The actual tapping point used
   cap 68 nF          
   resistance 0.5            ; Just a guess
   conductor 0.4e-2
   volts 20 kV
}

secondary {
   radius 0.20
   length 1.575
   height 0.995
   inductance 80mH   ; Use the measured inductance
   turns 939
   resistance 11.2      ; Measured resistance at DC.
   conductor 0.725e-3
}

END

For practical use, there are a number of input files distributed with the software. When creating an input file you can usually start with one of these and modify it as required.

Maintainer Paul Nicholson, tssp1611@abelian.org.